Vehicle motion control apparatus

• US 5,957,987 A
• Filed: 06/19/1997
• Issued: 09/28/1999
• Est. Priority Date: 06/19/1996
• Status: Expired due to Term

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Ito, Ken, Adachi, Kazutaka, Sudo, Hideki
• Primary Examiner(s): LOUIS JACQUES, JACQUES H
• Application Number:
  US08/879,219
• Time in Patent Office: 831 Days
• Field of Search: 701/36, 701/37, 701/41, 701/42, 701/43, 701/48, 701/38, 180/197, 180/415, 180/421, 180/446, 180/404, 180/410, 180/412, 180/422, 303/122, 303/140, 303/146, 303/147, 303/113.5, 280/142, 280/5.507, 280/5.51, 280/5.515, 280/5.514
• US Class Current: 701/41
• CPC Class Codes: B60T 2260/022 Rear-wheel steering; Four-wheel steering
• CPC Class Codes: B60T 2260/09 Complex systems; Conjoint control of two or more vehicle active control systems
• CPC Class Codes: B60T 8/1755 Brake regulation specially adapted to control the stability of the vehicle, e.g. taking into account yaw rate or transverse acceleration in a curve road vehicle drive control systems for control of driving stability otherwise than by controlling a particular sub-unit B60W30/02
• CPC Class Codes: B62D 7/159 characterised by computing methods or stabilisation processes or systems, e.g. responding to yaw rate, lateral wind, load, road condition

Abstract

An apparatus for controlling a motion of a vehicle supported on steered and non-steered road wheels. A target vehicle motion value is calculated based on the steering angle and vehicle speed to provide a predetermined response characteristic related to a vehicle plane behavior. A target steering angle value for the non-steered road wheel to realize the vehicle plane behavior is calculated according to the target vehicle motion value. The non-steered road wheels are steered according to the calculated target steering angle value. The damping characteristic of the response characteristic is decreased as the vehicle speed increases.

Claims

1. An apparatus for controlling a motion of a vehicle supported on steered and non-steered road wheels, comprising:

means for sensing vehicle operating conditions including steering angle and vehicle speed;

means for calculating a target vehicle motion value based on the sensed steering angle and vehicle speed to provide a predetermined response characteristic related to a vehicle plane behavior, the response characteristic having a damping characteristic;

means for calculating a target steering angle value for the non-steered road wheel to realize the vehicle plane behavior according to the target vehicle motion value;

means for steering the non-steered road wheels according to the calculated target steering angle value; and

means for decreasing the damping characteristic as the sensed vehicle speed increases.

2. The vehicle motion control apparatus as claimed in claim 1, wherein yaw rate is applied to the target vehicle motion value.

3. An apparatus for controlling a motion of a vehicle supported on steered and non-steered road wheels, comprising:

means for sensing steering angle;

means for sensing vehicle speed;

means for calculating a target vehicle motion value based on the sensed steering angle and vehicle speed to provide a predetermined vehicle plane behavior related response characteristic realized by a transfer function between the sensed steering angle and the target vehicle motion value, the transfer function having a damping coefficient;

means for calculating a target steering angle value for the non-steered road wheel to realize the vehicle plane behavior according to the target vehicle motion value;

means for steering the non-steered road wheels according to the calculated target steering angle value; and

means for decreasing the damping coefficient as the sensed vehicle speed increases.

4. The vehicle motion control apparatus as claimed in claim 3, wherein yaw rate is applied to the target vehicle motion value.

5. The vehicle motion control apparatus as claimed in claim 3, wherein the transfer function is defined as (an equation of the first degree)/(an equation of the second degree).

6. The vehicle motion control apparatus as claimed in claim 5, wherein yaw rate is applied to the target vehicle motion value.

7. An apparatus for controlling a motion of a vehicle supported on steered and non-steered road wheels, comprising:

detectors for sensing vehicle operating conditions including steering angle and vehicle speed;

means for calculating a target vehicle motion value based on the sensed steering angle and vehicle speed to provide a predetermined response characteristic related to a vehicle plane behavior, the response characteristic having a damping characteristic;

means for calculating a target steering angle value for the non-steered road wheel to realize the vehicle plane behavior according to the target vehicle motion value;

means for steering the non-steered road wheels according to the calculated target steering angle value; and

means for decreasing the damping characteristic as the sensed vehicle speed increases.

8. An apparatus for controlling a motion of a vehicle supported on steered and non-steered road wheels, comprising:

a first detector for sensing steering angle;

a second detector for sensing vehicle speed;

means for calculating a target vehicle motion value based on the sensed steering angle and vehicle speed to provide a predetermined vehicle plane behavior related response characteristic realized by a transfer function between the sensed steering angle and the target vehicle motion value, the transfer function having a damping coefficient;

means for calculating a target steering angle value for the non-steered road wheel to realize the vehicle plane behavior according to the target vehicle motion value;

means for steering the non-steered road wheels according to the calculated target steering angle value; and

means for decreasing the damping coefficient as the sensed vehicle speed increases.